78 A JOURNEY UP THE RIVER CONGO. 
invariably, no doubt, because it is there that most of their — 
food, such as grasshoppers and the exuvie of animals, 
usually lies. Still they are a curious instance of an 
arboreal type of bird gradually becoming terrestrial again. 
The great ground hornbill which is found pretty well 
all over Africa, except in the purely forest region, is a 
most exaggerated case, for it absolutely avoids the trees. 
Certain cuckoos, parrots, and woodpeckers become ground- 
loving birds in spite of their zygodactyle feet. I can 
imagine poor Dame Nature nearly losing her temper with, 
for instance, such a thing as a tree-duck. ‘ Whatever,” 
she must say, “made you take to living on trees when I 
had shaped and adapted your feet and your body for the 
water? Why can’t you know your own mind?” But 
the tree-duck and the ground hornbills and parrots are 
influenced by the same cause that makes a man who has 
been brought up as a land surveyor qualify himself for 
the Stage—the struggle for existence, the necessity of 
finding a place somewhere in life’s economy. 
Some such thoughts as these beguile my way through 
many a mile of forest and hill, till at length, arriving on 
the Congo bank at Ngoma, my attention is effectually 
diverted to the imposing spectacle of the Ngoma Falls. 
The standpoint from which one best views them is a little 
platform or quay protected by a breakwater, and pro- 
jecting somewhat into the river. Here lately stood an 
immense mass of precipitous rock; but Stanley, in 
opening a rapid route to Isangila, blasted the side of this 
cliff, and over the débris constructed a passable way. It 
was this that gained for him the name of Bula Matadi, or 
the stone-breaker, among the astonished natives. From 
this quay at Ngoma you command a splendid view. 
Nearly in front of you two branches of the Congo, 
separated by a long island, come rushing to a coalition, 
like two brothers whom a temporary obstacle has separated, 
or like two great political parties which, in view of the 
difficulties farther on, agree to coalesce, and carry off 
between them the lead that has hitherto been in the 
possession of a mild and temporising eddy. At the 
